A disenchanter is an annoying monster found in the deeper levels of the dungeons and in Gehennom. The random R at the Castle may be a disenchanter, but they are otherwise only randomly generated in Gehennom. Its attack can decrease the enchantment of weapons and armor (as well as doing an unthreatening amount of damage). Disenchanters are rather fast, so that most players without intrinsicspeed will find themselves confronted if they try to run a great distance away.

Hitting a disenchanter with a weapon can decrease the enchantment of the weapon.

Disenchanters are the deeper level equivalent of rust monsters. Disenchanters remove only positive enchantment; a disenchanter will not remove negative enchantment or cause an unenchanted item to gain negative enchantment.

Use ranged attacks. Be aware that your projectiles will be disenchanted; prefer spells or wands. In a game where you had many scrolls of enchant weapon, you might choose to throw from your pile of +7 daggers; for though the resulting +6 daggers will not stack, they are much preferable to disenchanting your artifacts or armor.

Unequip your weapon and punch it to death, or use an unenchanted weapon. Bear in mind that any gloves will be disenchanted if you hit with gloved hands.

Equip a junk weapon and hack it to death; pick-axes work well for this, as do some classes' starting secondaries.

Let your pet do the killing if it's strong enough, if your pet does not wield weapons.

Genocide. Because rust monsters are not much of a threat once the player reaches Gehennom, and blessed scrolls of genocide are best reserved for monsters whose entire class is difficult (liches, for example), disenchanters can be a good target for a single species (uncursed, if from a scroll) genocide.